Cooling system and apparatus for abrasive wheels



July 17, 1951 c. L. GARRISON COOLING SYSTEM AND APPARATUS FOR ABRASIVE WHEELS Filed July 8, 1948 ITS-El INVENTOR. Cfifiaro L Garrison BY I ATT

Patented July 17, 1951 COOLING SYSTEM AND APPARATUS FOR ABRA'SIVE WHEELS Clifford L. Garrison, Adrian, .Mioh., assignor to Oliver Instrument Company, Adrian, Mich, a

corporation .of .Michigan ApplicationJuly 8, 1948, Ser'ialNo. 37;577

(Cl. Sb-267.)

2 Claims. .1

This invention relates to an arrangement 'for cooling an abrasive wheel and the work being abraded or ground and more :especially to a system :of cooling a grinding wheel through the introduction of cooling fluid through the body of the grinding wheel.

:Heretofore it has been a general practice to cool .a rotating grinding wheel and the work throughthe'projection of a stream of cooling fluid such :as water against the exterior of wheel. Such a system :of cooling necessarily requires a comparatively large stream of water directed against the wheel periphery, the stream of water striking the wheel and the work resulting considerable splashing, this .form of cooling :heing diificult to control.

:The present invention embraces a system or arrangement wherein .a comparatively small stream of water. or other cooling lliquid introduced axially of the wheel, the water or other liquid being moved outwardly radially through the body of :the grinding wheel under the influence of centrifugal force set 'up by'th'e rotation of thewheel.

.Another object of the invention .is :the provisi'on of an arrangement whereina'comparatively small stream of cooling liquid is introduced into a chamber disposed centrally of the grinding wheel and wherein air is also introduced axially into :the wheel simultaneously with the cooling fluid whereby atomized particles of the cooling liquid are entrained in the air moving radial-1y through the body of the wheel under thejinfluence of centrifugal forces resulting in .anefficient cooling of the wheel and the work being ground through the utilization of fine globules of cooling fluid suspendedin air.

Another object of the invention resides. in the provision of an arrangement for cooling 2. grinding wheel and the work wherein air and particles of cooling liquid suspended therein are moved radially outwardly through .the :body of the wheel in combination with means ,for regulating the amount of water admitted into the the mist or particles of moisture drawn away from the "wheel to a point of discharge.

.Still another object of the invention resides in the provision of an arrangement for cooling an abrasive wheel wherein :acooling liquid is introduced centrally of the wheel andrdischarged substantially uniformly radially through the wheel so that all parts thereof are uniformly cooled.

Further objects and advantages are Within "the scope of this invention such as relate to "the arrangement, operation and vfunction of the .related elements :of the structure, to Various details of construction and to combinations .ofjpartselements perse, and to economies of manufacture and numerous other features as will be apparent from a consideration of the specification and drawing of a :form 'of the invention, which .may be preferred, in which:

Figure l'is an :elevational view of a portion :of a grinding machine illustrating an emodimcentof my invention;

Figure '2 is a ,verticalsectional view taken substantially on the .line 2--2 of Figure 1, and

Figure 3 is a vertical sectional view through the grinding wheel, the section :being taken substantially on the line 3-3 of Figure 2.

Referring [to the drawings in detail thezgrinding machine with which I have .il-ll'ustrated :an embodiment of my invention is inclusive of :a pedestal or frame it) upon which is supported :a movable table H upon which is mounted a Work carrying fixture l2 adapted to support the work or work piece W. It to be understood thatany form of WOI'K supporting means may be utilized in connection with the use of the-grinding wheel. Mounted upon the frame M of the grinding -machine is a casing or housing It within which is disposed an arbor-or shaft [5 journaled tor r0 tation upon anti-.irictio-n bearings if; carried by the housing. The shaft I5 is provided wtih radially extend-ing flange 18 which forms an abutment for positioning a grinding wheel Zll upon the shaft. The grinding wheel 29 is of the type wherein .the peripheral curved surface .25 is utilized as a grinding or abrasive surface for engagement withthe work W to beground, blltalt is to be understood that other types Iandrshapesof grinding wheel may be utilized in conjunction with the cooling arrangement of my invention. The grinding wheel Zfiis held in place by means of zacircular :disc or plate 21 which is drawn up into close engagement with the grinding wheel by means of a nut 22 which is threaded upona threaded portion .23 of a shaft or arbor it as particularly-shown'inFigure"2. The nutzi is pro with a peripheral channel or groove 2.9 which isin communication with the radially arranged passages 28.

I have provided means for supplying cooling liquid to the bore or chamber 2'1 in the arbor l5 which is inclusive of a tube 3| connected to a supply of cooling liquid as for example a water supply line. pipe or tube 3! is a fitting 32 having transparent or glazed sight openings 33 for the operator to visually ascertain the rate of flow of liquid from the pipe 3|. The fitting 32 is arranged to permit the passage of liquid therethrough and is provided with a boss portion 35 which is bored and threaded to receive a manually operable valve 36 which is formed with a knurled head portion 31 for ease of manipulation. The valve member 36 formed with a conically shaped end cooperating with a valve seat formed in the fitting 32, the valve being adapted to regulate or ,control the fiow of liquid or water through the Connected to the fitting 32 from the pipe 3|. lower end of the fitting 32 is a pipe or tube Ml having a portion 4 l axially arranged with respect to the axis of shaft or arbor l5 and extending into the chamber or bore 21 as shown in Figure 2.

By this arrangement the amount of water passing into the chamber 21 through the tube 40 may be regulated by manipulation of the valve mem- .ber. 36, the sight openings 33 advising the operator of the rate of flow of liquid through the fitting 32.

The uniplaner side walls of the grinding or abrasive wheel 23 are sealed or coated with a waterimpervious resin 43 or other suitable coating so as to direct particles of cooling liquid to the peripheral or working surface 25.

, I have provided means for enhancing the movement or moisture and air through the grinding wheel 20 and to carry away the water particles thrown from the wheel by establishing a zone of subatmospheric pressure adjacent the periphery of the wheel. To this end I have provided a shroud or housing 45 which surrounds a portion of the wheel as shown in Figures 1 and 2. The shroud 45 is provided with an outlet passage 46 which communicates with a manifold or duct ll, the latter being connected to a suction producing device or pump 48 which is adapted to be driven by a motor 49 or other suitable means. The suction producing device acts upon the zone adjacent the wheel 20 to draw away particles of moisture and material abraded by the wheel to discharge same at a point remote from the wheel. The housing 45 also serves as a guard for the grinding Wheel.

From the foregoing description of the invention, it will be seen that during rotation of the arbor I5 and the grinding wheel 20, water is admitted into the chamber 2'1 through the tube 4| and will be mixed with air in the chamber as the latter is open to the atmosphere. Due to the rotation of the grinding wheel 20 under the influence of centrifugal force, a radially directed suction or subatmospheric pressure is created within the body of the grinding wheel which Attached to the extremity of the causes the mixture of air and particles of water to move radially outwardly through the body of the wheel through the interstices existent between particles of abrasive making up the grinding wheel structure. The mixture of water particles and air is such that a mist is thrown from i the periphery of the wheel as the particles of water are fine enough to be suspended in the air as they leave the peripheral surface of the grinding wheel. The amount of water or other cooling liquid introduced into the chamber 21 may be accurately controlled or regulated by manipulation of the valve 36 in the fitting 32. I have found that a comparatively small amount of water delivered to the chamber 21 and there mixed with air to form a mist passing or percolating through the grinding wheel is very effective in the cooling of the wheel and the work W. By this means a very satisfactory control of the cooling of the wheel 20- and of the work is obtained. Through the utilization of the hood or shroud 45 and its connection with a vacuum or suction producing means 58, the major amount of mist thrown from the periphery of the grinding wheel 20 and materials abraded by the'wheel are carried away from the zone of the grinding operations. The impression of a zone of reduced pressure adjacent the major portion of the periphery of the grinding wheel augments the radial movement of water and air through the body of the wheel by reason of the differential pressure existent adjacent the shroud surrounding a portion of the grinding wheel. It should be noted that through the provision of the annular chamber or groove 29 the cooling liquid passing through the radial openings '28 will be substantially uniformly distributed through the chan nel 29 by centrifugal force, so that percolation or dispersion of cooling liquid through the wheel will be substantially uniform in directions radially of the grinding wheel. I have found that the arrangement of my invention is useful with various types of grinding or abrasive wheels in which there exist interstices or spaces-adjacent the grains of abrasive in the Wheel through which the cooling liquid may flow.

It is apparent that, within the scope of the invention, modifications and different arrangements may bemade other than is herein disclosed, and the present disclosure is illustrative merely, the invention comprehending all variations thereof.

What I claim is:

1. In combination, a shaft journalled for rotation in a support and having an axial bore in an end thereof open to the atmosphere for providing a mixing chamber, the said end of said shaft being provided with a peripheral groove adjacent the end thereof, a grinding wheel mounted on said end 'of said shaft over said groove, radial passages leading from said chamber .through said shaft to said groove, a conduit for introducing a liquid cooling medium into said chamber through the open end of said bore, the cross-sectional area of said conduit being substantially less than the cross-sectional area of said bore so that air in substantial amounts may readily enter said chamber around said conduit, whereby the centrifugal forces set up by the rotation of said grinding wheel will cause the liquid entering said chamber to become atom ized and entrained by the air entering said chamber so that finely divided particles ofcooling liquid'suspended in cooling air will be caused.

wheel to cool the latter, and suction means associated with said grinding wheel for creating a subatmospheric pressure adjacent a portion of the periphery of said wheel, whereby to accelerate the flow of said cooling mediums through said wheel and carry away the moisture thrown therefrom.

2. In combination, a shaft journalled for rotation in a support and having an axial bore in an end thereof open to the atmosphere for providing a cooling medium mixing chamber, the said end of said shaft being provided with a peripheral groove adjacent the end thereof, a grinding wheel mounted on said end of said shaft over said groove, the side faces of said wheel being coated with a liquid impervious material, radial passages leading from said chamber through said shaft to said groove, a conduit having an outlet through which a liquid cooling medium is introduced into said chamber through the open end of said bore, a valve in said conduit for controlling the flow of liquid therethrough, a fitting in said conduit having a sight opening to enable the rate of flow of the liquid through the conduit to be observed, the crosssectional area of said conduit at said outlet being substantially less than the cross-sectional area of said bore so that air in substantial amounts may readily enter said chamber around said outlet, whereby the centrifugal forces set up by the rotation of said grinding wheel will cause the liquid entering said chamber to become atomized and entrained by the air entering said chamber so that finely divided particles of cooling liquid suspended in cooling air will be caused to flow radially outwardly through the grinding wheel to cool the latter, and suction means associated with said grinding wheel for creating a subatmospheric pressure adjacent a portion of the periphery of said wheel, whereby to accelerate the flow of said cooling mediums through said wheel and carry away the moisture thrown therefrom.

CLIFFORD L. GARRISON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 164,692 Putnam et al June 22, 1875 376,854 Cavert Jan. 24, 1888 387,555 Cummings Aug. 7, 1888 500,561 Carpenter et a1 July 4, 1893 796,466 Stolzenberg Aug. 8, 1905 1,059,877 Keighley Apr. 22, 1913 1,491,515 Chase Apr. 2 1924 2,167,282 Murphy July 25, 1939 2,380,332 Scheer July 10, 1945 FOREIGN PATENTS Number Country Date 210,580 Great Britain Feb. 7, 1924 511,547 Germany Oct. 16, 1930 

